JPI issue after engine overhaul

[anthonydesmet]

I am in the final stretch of engine install after overhaul and when mech went to go run up engine, JPI is not powering up.  Power and ground look good.  JPI worked fine before overhaul 6 months ago.  It’s a 700.

thoughts?

[RobertGary1]

 Not powering up can only be power or ground. It will power up without any sensors working. Maybe a breaker got pulled??

 

-Robert 

[jaylw314]

When I first bought my Mooney, it came with a 711 (the primary version of the 700).  When I first started the engine with my CFI, I worriedly pointed out the 700 didn't turn on.  He reached over and flipped on the Radio Master switch.

It still puzzles me why a primary engine instrument is put on the avionics bus, but it would be worth double checking the mechanic didn't just run the engine without turning on the Radio Master?

[Aerodon]

The JPI is supposed to be grounded on the engine, seems to me there is a wire terminal looking for a home after the engine was changed....

Newer JPI harnesses have a ferrite ferule on the incoming power to remove voltage spikes - and then EDM900's and 930's are connected to the main bus not the avionics bus.

Aerodon 

[whiskytango]

I discovered that power for my JPI was not wired through a breaker, but had an in-line fuse that was buried in a wiring bundle above the control column.  You might want to check for a blown fuse somewhere.

[Missile=Awesome]

My 830 is on the Master not avionics master.  Has a separate breaker.

[ArtVandelay]

My 830 is on the Master not avionics master.  Has a separate breaker.

The certified versions should be on the master (just like the engine instruments it replaces), the 830 should be on the avionics.

From the installation manual:

“The avionics master switch will then be used to turn off the instrument during engine start-up.”

[Missile=Awesome]

5 minutes ago, ArtVandelay said:

The certified versions should be on the master (just like the engine instruments it replaces), the 830 should be on the avionics.

Art I just spoke with JPI and they CONFIRMED should be on the Master NOT the avionics master...

[kortopates]

15 minutes ago, Missile=Awesome said:

Art I just spoke with JPI and they CONFIRMED should be on the Master NOT the avionics master...

Yes, the way I understand it (I am not an avionics guy) is that the non-tso'd monitors are not approved for being on the main bus, just avionics. 

[PT20J]

4 minutes ago, kortopates said:

Yes, the way I understand it (I am not an avionics guy) is that the non-tso'd monitors are not approved for being on the main bus, just avionics. 

All I can add is that my factory-installed EDM 700 is on the avionics bus.

Skip

[ArtVandelay]

Art I just spoke with JPI and they CONFIRMED should be on the Master NOT the avionics master...

Somebody is confused, either you or JPI.
Again, the certified versions (9XX models) vs 730/830 models.
From their installation manual:

[Missile=Awesome]

I am going to go with what the contact at the mfr said...and he said “MASTER for 830”. NOT Avionics master.  I posed the question with my model asking Master or Avionics Master.  He said MASTER.  I joked that everything on the internet is correct so it must be the Avionics Master...He said “Not everything you read on the internet is correct”...

The end.

[kortopates]

im guessing they had voltage drop problems and changed it with some revision...excerpt from my manual above says why it goes all the way back to the solenoid.

everything on the internet isnt true?

Mike

let's not confuse the tso's 9xx series installations with the non-tso'd 7xx 8xx installations. They are entirely different since the 7xx/8xx does not have the approvals.

Tom already posted the relevant paragraph from the EDM 7xx/8xx FAA Approved install manual that clearly states that these units should be connected to the Avionics master - it even says if the aircraft doesn't have an Avionics master switch the installer should install such a switch and that the power wire should be proctected by a 5 amp CB - or a 2 amp slow blow inline fuse. Personally I wouldn't accept an inline fuse but it's allowable.

 

Phone calls with tech support have never been considered even remotely acceptable and certainly not approved data to the FAA. (I'd like to see a log book entry suggesting that!). Of course any guidance like that would have to followed up with tech support mailing or emailing the FAA Approved documentation to back up the telephone conversation. Of course in this case that's superfluous since JPI has all these doc's on the web for all that can access and read them. The STC FAA Approved installation data is approved data to the FAA.

 

 

Sent from my iPhone using Tapatalk

[Bartman]

I had problems with my 700 immediately after installation of my engine this year. The ground was hooked up to the engine baffle and the JPI-700 did not like that. After we hooked it up to the engine it worked fine, except for the #3 EGT probe that did not survive. 

[ArtVandelay]

I am going to go with what the contact at the mfr said...and he said “MASTER for 830”. NOT Avionics master.  I posed the question with my model asking Master or Avionics Master.  He said MASTER.  I joked that everything on the internet is correct so it must be the Avionics Master...He said “Not everything you read on the internet is correct”...
The end.

You should have asked him why their own installation manual on their website disagrees with him, this isn’t from the “internet”, this is from his company engineers. JPI service doesn’t have a good reputation...I’ll guess this is another reason.

[MikeOH]

18 minutes ago, ArtVandelay said:

You should have asked him why their own installation manual on their website disagrees with him, this isn’t from the “internet”, this is from his company engineers. JPI service doesn’t have a good reputation...I’ll guess this is another reason.

Not to mention the OP specifically said he had a 700, NOT an 830.

[carusoam]

Some of this is a challenge for the electronic device itself....

Starting the engine, and then alternator... can put some spikes in the voltage....

The 900 series JPI has been designed with these spikes being a normal task for a primary engine monitor... it is on before the engine starts...

The first thing we want to see is the OilP come up, or we are shutting down ASAP... the engine monitor has to be on line for this event...

The 700 and 800 series don’t need to put up with this... but some 700 series are primary instruments for some CHT and EGT applications....

It is possible, that these devices are designed to handle the start-up spikes in voltage...  but, it’s an expensive device to put through the extra start-up challenges if not required...

My 700 series is on the avionics master... and automatically records voltage from the moment it turns on...  

 

If you fry an electronic device on your instrument panel... is anyone going to care?

The device either gets power, or it doesn’t... look to see where the JPI is grounded to, and gets its power from...

Let The volt meter do the magic...  

MS doesn’t have a JPI guy... but we do have a great tech guy from that other engine monitor company...

Best regards,

-a-

[Missile=Awesome]

14 hours ago, MikeOH said:

Not to mention the OP specifically said he had a 700, NOT an 830.

Had a 700 in plane that was upgraded by us.  The 730 and 830 are direct upgrade paths for the 700 and 800 so thought it might be relevant information for original poster.  What it resulted in was a vomiting and finger pointing by members in my direction.  The 700 was installed for years.  I will get back to you on the longevity of the 830 as installed.  

Sorry for giving everyone nightmares.  My eyes are WIDE OPEN.  Good luck sorting (original poster) Sorry for the shitshow.